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Cosmic superstrings are produced towards the end of the brane inflation. If the string tension is low enough, loops tend to be relatively long-lived. The resultant string network is expected to contain many loops which are smaller than typical Galactic scales. Cosmic expansion damps the center of mass motion of the loops which then cluster like cold dark matter. Loops will lens stars within the galaxy and local group. We explore microlensing of stars as a tool to detect and to characterize some of the fundamental string and string network properties, including the dimensionless string tension $G mu/c^2$ and the density of string loops within the Galaxy. As $G mu to 0$ the intrinsic microlensing rate diverges as $1/sqrt{G mu}$ but experimental detection will be limited by shortness of the lensing timescale and/or smallness of the bending angle which each vary $propto G mu$. We find that detection is feasible for a range of tensions. As an illustration, the planned optical astrometric survey mission, Gaia, should be able to detect numerous microlensing events for string networks with tensions $10^{-10} simless G mu simless 10^{-6}$. A null result for optical microlensing implies $G mu simless 10^{-10}$. If lensing of a given source is observed it will repeat because the internal motions of the loop are relativistic but the center of mass motion may be much smaller, of order the halo velocity. This distinctive hallmark $sim 1000$ repetitions, suggests a useful method for confirmation of a potential lensing detection.
Gravitational waves (GWs) are one of the key signatures of cosmic strings. If GWs from cosmic strings are detected in future experiments, not only their existence can be confirmed but also their properties might be probed. In this paper, we study the
We study the network of Type-I cosmic strings using the field-theoretic numerical simulations in the Abelian-Higgs model. For Type-I strings, the gauge field plays an important role, and thus we find that the correlation length of the strings is stro
We consider the femto-lensing due to a cosmic string. If a cosmic string with the deficit angle $Deltasim 100$ [femto-arcsec] $sim10^{-18}$ [rad] exists around the line of sight to a gamma-ray burst, we may observe characteristic interference pattern
To understand the properties of a possible cosmic string network requires knowledge of the structures on long strings, which control the breaking off of smaller loops. These structures are influenced by backreaction due to gravitational wave emission
We consider the evolution of a cosmic string loop that is captured by a much more massive and compact black hole. We show that after several reconnections that produce ejections of smaller loops, the loop that remains bound to the black hole moves on